Managing concurrent multi-rat uplink transmissions at a user equipment

ABSTRACT

In an embodiment, a UE receives a first uplink grant for a first RAT (e.g., 5G NR) and a second uplink grant for a second RAT (e.g., LTE). In one embodiment, the UE schedules an uplink transmission on the first RAT (e.g., by selectively dropping the uplink transmission on particular resource blocks) so as to manage an amount of time that is based on concurrent uplink transmissions on both the first and second RATs are performed. In another embodiment, the UE establishes a first period of time where a BSR transmitted by the UE on the first RAT is adjusted based on scheduling of concurrent uplink multi-RAT transmissions, and a second period of time where no BSR is transmitted by the UE on the first RAT based where concurrent uplink transmissions on both the first and second RATs are not permitted to be scheduled.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application for patent is a Continuation of Non-Provisionalpatent application Ser. No. 16/810,383, entitled “MANAGING CONCURRENTMULTI-RAT UPLINK TRANSMISSIONS AT A USER EQUIPMENT” filed Mar. 5, 2020,which in turn claims the benefit of Provisional Patent Application No.62/876,439 entitled “MANAGING CONCURRENT MULTI-RAT UPLINK TRANSMISSIONSAT A USER EQUIPMENT” filed Jul. 19, 2019, each of which is assigned tothe assignee hereof and hereby expressly incorporated herein byreference in its entirety.

TECHNICAL FIELD

Various aspects described herein generally relate to managing concurrentmulti-RAT uplink transmissions at a user equipment.

BACKGROUND

Wireless communication systems have developed through variousgenerations, including a first-generation analog wireless phone service(1G), a second-generation (2G) digital wireless phone service (includinginterim 2.5G and 2.75G networks), a third-generation (3G) high speeddata, Internet-capable wireless service and a fourth-generation (4G)service (e.g., Long Term Evolution (LTE) or WiMax). There are presentlymany different types of wireless communication systems in use, includingCellular and Personal Communications Service (PCS) systems. Examples ofknown cellular systems include the cellular Analog Advanced Mobile PhoneSystem (AMPS), and digital cellular systems based on Code DivisionMultiple Access (CDMA), Frequency Division Multiple Access (FDMA), TimeDivision Multiple Access (TDMA), the Global System for Mobile access(GSM) variation of TDMA, etc.

A fifth generation (5G) mobile standard calls for higher data transferspeeds, greater numbers of connections, and better coverage, among otherimprovements. The 5G standard, according to the Next Generation MobileNetworks Alliance, is designed to provide data rates of several tens ofmegabits per second to each of tens of thousands of users, with 1gigabit per second to tens of workers on an office floor. Severalhundreds of thousands of simultaneous connections should be supported inorder to support large sensor deployments. Consequently, the spectralefficiency of 5G mobile communications should be significantly enhancedcompared to the current 4G standard. Furthermore, signaling efficienciesshould be enhanced and latency should be substantially reduced comparedto current standards.

Some wireless communication networks, such as 5G, support operation atvery high and even extremely-high frequency (EHF) bands, such asmillimeter wave (mmW) frequency bands (generally, wavelengths of 1 mm to10 mm, or 30 to 300 GHz). These extremely high frequencies may supportvery high throughput such as up to six gigabits per second (Gbps). Oneof the challenges for wireless communication at very high or extremelyhigh frequencies, however, is that a significant propagation loss mayoccur due to the high frequency. As the frequency increases, thewavelength may decrease, and the propagation loss may increase as well.At mmW frequency bands, the propagation loss may be severe. For example,the propagation loss may be on the order of 22 to 27 dB, relative tothat observed in either the 2.4 GHz, or 5 GHz bands.

SUMMARY

An embodiment is directed to a method of operating a user equipment(UE), comprising receiving a first uplink grant for a first radio accesstechnology (RAT), receiving a second uplink grant for a second RAT,determining an amount of time, over a window of time, that is based onconcurrent uplink transmissions on both the first and second RATs areperformed, determining that the amount of time will exceed a timethreshold if an uplink transmission is performed on the first RAT, andscheduling the uplink transmission on the first RAT based on the amountof time so as to maintain the amount of time where concurrent uplinktransmissions on both the first and second RATs are performed to be lessthan or equal to the time threshold.

Another embodiment is directed to a method of operating a user equipment(UE), comprising receiving a first uplink grant for a first radio accesstechnology (RAT), receiving a second uplink grant for a second RAT, andestablishing a first period of time where a buffer status report (BSR)transmitted by the UE on the first RAT is adjusted to reflect an amountof data that can be drained in an amount of time where concurrent uplinktransmissions on both the first and second RATs are permitted to bescheduled, and establishing a second period of time where no BSR istransmitted by the UE on the first RAT based on a time thresholdassociated with an amount of time where concurrent uplink transmissionson both the first and second RATs are not permitted to be scheduled

Another embodiment is directed to a user equipment (UE), comprising amemory, at least one transceiver, and at least one processor coupled tothe memory and the at least one transceiver and configured to receive afirst uplink grant for a first radio access technology (RAT), receive asecond uplink grant for a second RAT, determine an amount of time, overa window of time, that is based on concurrent uplink transmissions onboth the first and second RATs are performed, determine that the amountof time will exceed a time threshold if an uplink transmission isperformed on the first RAT, and schedule the uplink transmission on thefirst RAT based on the amount of time so as to maintain the amount oftime where concurrent uplink transmissions on both the first and secondRATs are performed to be less than or equal to the time threshold.

Another embodiment is directed to a user equipment (UE), comprising amemory, at least one transceiver, and at least one processor coupled tothe memory and the at least one transceiver and configured to receive afirst uplink grant for a first radio access technology (RAT), receive asecond uplink grant for a second RAT, establish a first period of timewhere a buffer status report (BSR) transmitted by the UE on the firstRAT is adjusted to reflect an amount of data that can be drained in anamount of time where concurrent uplink transmissions on both the firstand second RATs are permitted to be scheduled, and establish a secondperiod of time where no BSR is transmitted by the UE on the first RATbased on a time threshold associated with an amount of time whereconcurrent uplink transmissions on both the first and second RATs arenot permitted to be scheduled.

Another embodiment is directed to a user equipment (UE), comprisingmeans for receiving a first uplink grant for a first radio accesstechnology (RAT), means for receiving a second uplink grant for a secondRAT, means for determining an amount of time, over a window of time,that is based on concurrent uplink transmissions on both the first andsecond RATs are performed, means for determining that the amount of timewill exceed a time threshold if an uplink transmission is performed onthe first RAT, and means for scheduling the uplink transmission on thefirst RAT based on the amount of time so as to maintain the amount oftime where concurrent uplink transmissions on both the first and secondRATs are performed to be less than or equal to the time threshold.

Another embodiment is directed to a user equipment (UE), comprisingmeans for receiving a first uplink grant for a first radio accesstechnology (RAT), means for receiving a second uplink grant for a secondRAT, means for establishing a first period of time where a buffer statusreport (BSR) transmitted by the UE on the first RAT is adjusted toreflect an amount of data that can be drained in an amount of time whereconcurrent uplink transmissions on both the first and second RATs arepermitted to be scheduled, and means for establishing a second period oftime where no BSR is transmitted by the UE on the first RAT based on atime threshold associated with an amount of time where concurrent uplinktransmissions on both the first and second RATs are not permitted to bescheduled.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the various aspects described herein andmany attendant advantages thereof will be readily obtained as the samebecomes better understood by reference to the following detaileddescription when considered in connection with the accompanying drawingswhich are presented solely for illustration and not limitation, and inwhich:

FIG. 1 illustrates an exemplary wireless communications system,according to various aspects.

FIGS. 2A and 2B illustrate example wireless network structures,according to various aspects.

FIG. 3A illustrates an exemplary base station and an exemplary userequipment (UE) in an access network, according to various aspects.

FIG. 3B illustrates an exemplary server according to various aspects.

FIG. 4 illustrates an exemplary wireless communications system accordingto various aspects of the disclosure.

FIG. 5 illustrates an exemplary process of managing concurrent multi-RATuplink transmissions at a UE.

FIGS. 6A-6B illustrate scenarios where timings for radio accesstechnologies (RATs) 1 and 2 are offset from each other by a half-slot.

FIGS. 7A-7B illustrate additional scenarios where timings for RATs 1 and2 are offset from each other by a half-slot.

FIGS. 7C-7D illustrate scenarios where timings for RATs 1 and 2 areoffset from each other by a half-slot whereby RAT 1 corresponds to 5G NR(or simply NR) and RAT 2 corresponds to LTE.

FIG. 8 illustrates another exemplary process of managing concurrentmulti-RAT uplink transmissions at a UE.

DETAILED DESCRIPTION

Various aspects described herein generally relate to managing concurrentmulti-RAT uplink transmissions at a user equipment.

These and other aspects are disclosed in the following description andrelated drawings to show specific examples relating to exemplaryaspects. Alternate aspects will be apparent to those skilled in thepertinent art upon reading this disclosure, and may be constructed andpracticed without departing from the scope or spirit of the disclosure.Additionally, well-known elements will not be described in detail or maybe omitted so as to not obscure the relevant details of the aspectsdisclosed herein.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any aspect described herein as “exemplary”is not necessarily to be construed as preferred or advantageous overother aspects. Likewise, the term “aspects” does not require that allaspects include the discussed feature, advantage, or mode of operation.

The terminology used herein describes particular aspects only and shouldnot be construed to limit any aspects disclosed herein. As used herein,the singular forms “a,” “an,” and “the” are intended to include theplural forms as well, unless the context clearly indicates otherwise.Those skilled in the art will further understand that the terms“comprises,” “comprising,” “includes,” and/or “including,” as usedherein, specify the presence of stated features, integers, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

Further, various aspects may be described in terms of sequences ofactions to be performed by, for example, elements of a computing device.Those skilled in the art will recognize that various actions describedherein can be performed by specific circuits (e.g., an applicationspecific integrated circuit (ASIC)), by program instructions beingexecuted by one or more processors, or by a combination of both.Additionally, these sequences of actions described herein can beconsidered to be embodied entirely within any form of non-transitorycomputer-readable medium having stored thereon a corresponding set ofcomputer instructions that upon execution would cause an associatedprocessor to perform the functionality described herein. Thus, thevarious aspects described herein may be embodied in a number ofdifferent forms, all of which have been contemplated to be within thescope of the claimed subject matter. In addition, for each of theaspects described herein, the corresponding form of any such aspects maybe described herein as, for example, “logic configured to” and/or otherstructural components configured to perform the described action.

As used herein, the terms “user equipment” (or “UE”), “user device,”“user terminal,” “client device,” “communication device,” “wirelessdevice,” “wireless communications device,” “handheld device,” “mobiledevice,” “mobile terminal,” “mobile station,” “handset,” “accessterminal,” “subscriber device,” “subscriber terminal,” “subscriberstation,” “terminal,” and variants thereof may interchangeably refer toany suitable mobile or stationary device that can receive wirelesscommunication and/or navigation signals. These terms are also intendedto include devices which communicate with another device that canreceive wireless communication and/or navigation signals such as byshort-range wireless, infrared, wireline connection, or otherconnection, regardless of whether satellite signal reception, assistancedata reception, and/or position-related processing occurs at the deviceor at the other device. In addition, these terms are intended to includeall devices, including wireless and wireline communication devices, thatcan communicate with a core network via a radio access network (RAN),and through the core network the UEs can be connected with externalnetworks such as the Internet and with other UEs. Of course, othermechanisms of connecting to the core network and/or the Internet arealso possible for the UEs, such as over a wired access network, awireless local area network (WLAN) (e.g., based on IEEE 802.11, etc.)and so on. UEs can be embodied by any of a number of types of devicesincluding but not limited to printed circuit (PC) cards, compact flashdevices, external or internal modems, wireless or wireline phones,smartphones, tablets, tracking devices, asset tags, and so on. Acommunication link through which UEs can send signals to a RAN is calledan uplink channel (e.g., a reverse traffic channel, a reverse controlchannel, an access channel, etc.). A communication link through whichthe RAN can send signals to UEs is called a downlink or forward linkchannel (e.g., a paging channel, a control channel, a broadcast channel,a forward traffic channel, etc.). As used herein the term trafficchannel (TCH) can refer to either an uplink/reverse or downlink/forwardtraffic channel.

According to various aspects, FIG. 1 illustrates an exemplary wirelesscommunications system 100. The wireless communications system 100 (whichmay also be referred to as a wireless wide area network (WWAN)) mayinclude various base stations 102 and various UEs 104. The base stations102 may include macro cells (high power cellular base stations) and/orsmall cells (low power cellular base stations), wherein the macro cellsmay include Evolved NodeBs (eNBs), where the wireless communicationssystem 100 corresponds to an LTE network, or gNodeBs (gNBs), where thewireless communications system 100 corresponds to a 5G network or acombination of both, and the small cells may include femtocells,picocells, microcells, etc.

The base stations 102 may collectively form a Radio Access Network (RAN)and interface with an Evolved Packet Core (EPC) or Next Generation Core(NGC) through backhaul links. In addition to other functions, the basestations 102 may perform functions that relate to one or more oftransferring user data, radio channel ciphering and deciphering,integrity protection, header compression, mobility control functions(e.g., handover, dual connectivity), inter-cell interferencecoordination, connection setup and release, load balancing, distributionfor non-access stratum (NAS) messages, NAS node selection,synchronization, RAN sharing, multimedia broadcast multicast service(MBMS), subscriber and equipment trace, RAN information management(RIM), paging, positioning, and delivery of warning messages. The basestations 102 may communicate with each other directly or indirectly(e.g., through the EPC/NGC) over backhaul links 134, which may be wiredor wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Eachof the base stations 102 may provide communication coverage for arespective geographic coverage area 110. In an aspect, although notshown in FIG. 1 , geographic coverage areas 110 may be subdivided into aplurality of cells (e.g., three), or sectors, each cell corresponding toa single antenna or array of antennas of a base station 102. As usedherein, the term “cell” or “sector” may correspond to one of a pluralityof cells of a base station 102, or to the base station 102 itself,depending on the context.

While neighboring macro cell geographic coverage areas 110 may partiallyoverlap (e.g., in a handover region), some of the geographic coverageareas 110 may be substantially overlapped by a larger geographiccoverage area 110. For example, a small cell base station 102′ may havea geographic coverage area 110′ that substantially overlaps with thegeographic coverage area 110 of one or more macro cell base stations102. A network that includes both small cell and macro cells may beknown as a heterogeneous network. A heterogeneous network may alsoinclude Home eNBs (HeNBs), which may provide service to a restrictedgroup known as a closed subscriber group (CSG). The communication links120 between the base stations 102 and the UEs 104 may include uplink(UL) (also referred to as reverse link) transmissions from a UE 104 to abase station 102 and/or downlink (DL) (also referred to as forward link)transmissions from a base station 102 to a UE 104. The communicationlinks 120 may use MIMO antenna technology, including spatialmultiplexing, beamforming, and/or transmit diversity. The communicationlinks may be through one or more carriers. Allocation of carriers may beasymmetric with respect to DL and UL (e.g., more or less carriers may beallocated for DL than for UL).

The wireless communications system 100 may further include a wirelesslocal area network (WLAN) access point (AP) 150 in communication withWLAN stations (STAs) 152 via communication links 154 in an unlicensedfrequency spectrum (e.g., 5 GHz). When communicating in an unlicensedfrequency spectrum, the WLAN STAs 152 and/or the WLAN AP 150 may performa clear channel assessment (CCA) prior to communicating in order todetermine whether the channel is available.

The small cell base station 102′ may operate in a licensed and/or anunlicensed frequency spectrum. When operating in an unlicensed frequencyspectrum, the small cell base station 102′ may employ LTE or 5Gtechnology and use the same 5 GHz unlicensed frequency spectrum as usedby the WLAN AP 150. The small cell base station 102′, employing LTE/5Gin an unlicensed frequency spectrum, may boost coverage to and/orincrease capacity of the access network. LTE in an unlicensed spectrummay be referred to as LTE-unlicensed (LTE-U), licensed assisted access(LAA), or MulteFire.

The wireless communications system 100 may further include a mmW basestation 180 that may operate in mmW frequencies and/or near mmWfrequencies in communication with a UE 182. Extremely high frequency(EHF) is part of the RF in the electromagnetic spectrum. EHF has a rangeof 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10millimeters. Radio waves in this band may be referred to as a millimeterwave. Near mmW may extend down to a frequency of 3 GHz with a wavelengthof 100 millimeters. The super high frequency (SHF) band extends between3 GHz and 30 GHz, also referred to as centimeter wave. Communicationsusing the mmW/near mmW radio frequency band have high path loss and arelatively short range. The mmW base station 180 may utilize beamforming184 with the UE 182 to compensate for the extremely high path loss andshort range. Further, it will be appreciated that in alternativeconfigurations, one or more base stations 102 may also transmit usingmmW or near mmW and beamforming. Accordingly, it will be appreciatedthat the foregoing illustrations are merely examples and should not beconstrued to limit the various aspects disclosed herein.

The wireless communications system 100 may further include one or moreUEs, such as UE 190, that connects indirectly to one or morecommunication networks via one or more device-to-device (D2D)peer-to-peer (P2P) links. In the embodiment of FIG. 1 , UE 190 has a D2DP2P link 192 with one of the UEs 104 connected to one of the basestations 102 (e.g., through which UE 190 may indirectly obtain cellularconnectivity) and a D2D P2P link 194 with WLAN STA 152 connected to theWLAN AP 150 (through which UE 190 may indirectly obtain WLAN-basedInternet connectivity). In an example, the D2D P2P links 192-194 may besupported with any well-known D2D radio access technology (RAT), such asLTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth, and so on.

According to various aspects, FIG. 2A illustrates an example wirelessnetwork structure 200. For example, an NGC 210 can be viewedfunctionally as control plane functions 214 (e.g., UE registration,authentication, network access, gateway selection, etc.), and user planefunctions 212 (e.g., UE gateway function, access to data networks,Internet protocol (IP) routing, etc.), which operate cooperatively toform the core network. User plane interface (NG-U) 213 and control planeinterface (NG-C) 215 connect the gNB 222 to the NGC 210 and specificallyto the control plane functions 214 and user plane functions 212. In anadditional configuration, an eNB 224 may also be connected to the NGC210 via NG-C 215 to the control plane functions 214 and NG-U 213 to userplane functions 212. Further, eNB 224 may directly communicate with gNB222 via a backhaul connection 223. Accordingly, in some configurations,the New RAN 220 may only have one or more gNBs 222, while otherconfigurations include one or more of both eNBs 224 and gNBs 222. EithergNB 222 or eNB 224 may communicate with UEs 240 (e.g., any of the UEsdepicted in FIG. 1 , such as UEs 104, UE 152, UE 182, UE 190, etc.).Another optional aspect may include a location server 230 that may be incommunication with the NGC 210 to provide location assistance for UEs240. The location server 230 can be implemented as a plurality ofstructurally separate servers, or alternately may each correspond to asingle server. The location server 230 can be configured to support oneor more location services for UEs 240 that can connect to the locationserver 230 via the core network, NGC 210, and/or via the Internet (notillustrated). Further, the location server 230 may be integrated into acomponent of the core network, or alternatively may be external to thecore network.

According to various aspects, FIG. 2B illustrates another examplewireless network structure 250. For example, an NGC 260 can be viewedfunctionally as control plane functions, an access and mobilitymanagement function (AMF) 264 and user plane functions, and a sessionmanagement function (SMF) 262, which operate cooperatively to form thecore network. User plane interface 263 and control plane interface 265connect the eNB 224 to the NGC 260 and specifically to AMF 264 and SMF262. In an additional configuration, a gNB 222 may also be connected tothe NGC 260 via control plane interface 265 to AMF 264 and user planeinterface 263 to SMF 262. Further, eNB 224 may directly communicate withgNB 222 via the backhaul connection 223, with or without gNB directconnectivity to the NGC 260. Accordingly, in some configurations, theNew RAN 220 may only have one or more gNBs 222, while otherconfigurations include one or more of both eNBs 224 and gNBs 222. EithergNB 222 or eNB 224 may communicate with UEs 240 (e.g., any of the UEsdepicted in FIG. 1 , such as UEs 104, UE 182, UE 190, etc.). Anotheroptional aspect may include a location management function (LMF) 270,which may be in communication with the NGC 260 to provide locationassistance for UEs 240. The LMF 270 can be implemented as a plurality ofseparate servers (e.g., physically separate servers, different softwaremodules on a single server, different software modules spread acrossmultiple physical servers, etc.), or alternately may each correspond toa single server. The LMF 270 can be configured to support one or morelocation services for UEs 240 that can connect to the LMF 270 via thecore network, NGC 260, and/or via the Internet (not illustrated).

According to various aspects, FIG. 3A illustrates an exemplary basestation (BS) 310 (e.g., an eNB, a gNB, a small cell AP, a WLAN AP, etc.)in communication with an exemplary UE 350 (e.g., any of the UEs depictedin FIG. 1 , such as UEs 104, UE 152, UE 182, UE 190, etc.) in a wirelessnetwork. In the DL, IP packets from the core network (NGC 210/EPC 260)may be provided to a controller/processor 375. The controller/processor375 implements functionality for a radio resource control (RRC) layer, apacket data convergence protocol (PDCP) layer, a radio link control(RLC) layer, and a medium access control (MAC) layer. Thecontroller/processor 375 provides RRC layer functionality associatedwith broadcasting of system information (e.g., master information block(MIB), system information blocks (SIBs)), RRC connection control (e.g.,RRC connection paging, RRC connection establishment, RRC connectionmodification, and RRC connection release), inter-RAT mobility, andmeasurement configuration for UE measurement reporting; PDCP layerfunctionality associated with header compression/decompression, security(ciphering, deciphering, integrity protection, integrity verification),and handover support functions; RLC layer functionality associated withthe transfer of upper layer packet data units (PDUs), error correctionthrough automatic repeat request (ARQ), concatenation, segmentation, andreassembly of RLC service data units (SDUs), re-segmentation of RLC dataPDUs, and reordering of RLC data PDUs; and MAC layer functionalityassociated with mapping between logical channels and transport channels,scheduling information reporting, error correction, priority handling,and logical channel prioritization.

The transmit (TX) processor 316 and the receive (RX) processor 370implement Layer-1 functionality associated with various signalprocessing functions. Layer-1, which includes a physical (PHY) layer,may include error detection on the transport channels, forward errorcorrection (FEC) coding/decoding of the transport channels,interleaving, rate matching, mapping onto physical channels,modulation/demodulation of physical channels, and MIMO antennaprocessing. The TX processor 316 handles mapping to signalconstellations based on various modulation schemes (e.g., binaryphase-shift keying (BPSK), quadrature phase-shift keying (QPSK),M-phase-shift keying (M-PSK), M-quadrature amplitude modulation(M-QAM)). The coded and modulated symbols may then be split intoparallel streams. Each stream may then be mapped to an orthogonalfrequency-division multiplexing (OFDM) subcarrier, multiplexed with areference signal (e.g., pilot) in the time and/or frequency domain, andthen combined together using an inverse fast Fourier transform (IFFT) toproduce a physical channel carrying a time domain OFDM symbol stream.The OFDM stream is spatially precoded to produce multiple spatialstreams. Channel estimates from a channel estimator 374 may be used todetermine the coding and modulation scheme, as well as for spatialprocessing. The channel estimate may be derived from a reference signaland/or channel condition feedback transmitted by the UE 350. Eachspatial stream may then be provided to one or more different antennas320 via a separate transmitter 318 a. Each transmitter 318 a maymodulate an RF carrier with a respective spatial stream fortransmission.

At the UE 350, each receiver 354 a receives a signal through itsrespective antenna 352. Each receiver 354 a recovers informationmodulated onto an RF carrier and provides the information to the RXprocessor 356. The TX processor 368 and the RX processor 356 implementLayer-1 functionality associated with various signal processingfunctions. The RX processor 356 may perform spatial processing on theinformation to recover any spatial streams destined for the UE 350. Ifmultiple spatial streams are destined for the UE 350, they may becombined by the RX processor 356 into a single OFDM symbol stream. TheRX processor 356 then converts the OFDM symbol stream from thetime-domain to the frequency domain using a fast Fourier transform(FFT). The frequency domain signal comprises a separate OFDM symbolstream for each subcarrier of the OFDM signal. The symbols on eachsubcarrier, and the reference signal, are recovered and demodulated bydetermining the most likely signal constellation points transmitted bythe base station 310. These soft decisions may be based on channelestimates computed by the channel estimator 358. The soft decisions arethen decoded and de-interleaved to recover the data and control signalsthat were originally transmitted by the base station 310 on the physicalchannel. The data and control signals are then provided to theprocessing system 359, which implements Layer-3 and Layer-2functionality.

The processing system 359 can be associated with a memory 360 thatstores program codes and data. The memory 360 may be referred to as anon-transitory computer-readable medium. In the UL, the processingsystem 359 provides demultiplexing between transport and logicalchannels, packet reassembly, deciphering, header decompression, andcontrol signal processing to recover IP packets from the core network.The processing system 359 is also responsible for error detection.

Similar to the functionality described in connection with the DLtransmission by the base station 310, the processing system 359 providesRRC layer functionality associated with system information (e.g., MIB,SIBs) acquisition, RRC connections, and measurement reporting; PDCPlayer functionality associated with header compression/decompression,and security (ciphering, deciphering, integrity protection, integrityverification); RLC layer functionality associated with the transfer ofupper layer PDUs, error correction through ARQ, concatenation,segmentation, and reassembly of RLC SDUs, re-segmentation of RLC dataPDUs, and reordering of RLC data PDUs; and MAC layer functionalityassociated with mapping between logical channels and transport channels,multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing ofMAC SDUs from TBs, scheduling information reporting, error correctionthrough hybrid automatic repeat request (HARQ), priority handling, andlogical channel prioritization.

Channel estimates derived by the channel estimator 358 from a referencesignal or feedback transmitted by the base station 310 may be used bythe TX processor 368 to select the appropriate coding and modulationschemes, and to facilitate spatial processing. The spatial streamsgenerated by the TX processor 368 may be provided to different antenna352 via separate transmitters 354 b. Each transmitter 354 b may modulatean RF carrier with a respective spatial stream for transmission. In anaspect, the transmitters 354 b and the receivers 354 a may be one ormore transceivers, one or more discrete transmitters, one or morediscrete receivers, or any combination thereof.

The UL transmission is processed at the base station 310 in a mannersimilar to that described in connection with the receiver function atthe UE 350. Each receiver 318 b receives a signal through its respectiveantenna 320. Each receiver 318 b recovers information modulated onto anRF carrier and provides the information to a RX processor 370. In anaspect, the transmitters 318 a and the receivers 318 b may be one ormore transceivers, one or more discrete transmitters, one or morediscrete receivers, or any combination thereof.

The processing system 375 can be associated with a memory 376 thatstores program codes and data. The memory 376 may be referred to as anon-transitory computer-readable medium. In the UL, the processingsystem 375 provides demultiplexing between transport and logicalchannels, packet reassembly, deciphering, header decompression, controlsignal processing to recover IP packets from the UE 350. IP packets fromthe processing system 375 may be provided to the core network. Theprocessing system 375 is also responsible for error detection.

FIG. 3B illustrates an exemplary server 300B. In an example, the server300B may correspond to one example configuration of the location server230 described above. In FIG. 3B, the server 300B includes a processor301B coupled to volatile memory 302B and a large capacity nonvolatilememory, such as a disk drive 303B. The server 300B may also include afloppy disc drive, compact disc (CD) or DVD disc drive 306B coupled tothe processor 301B. The server 300B may also include network accessports 304B coupled to the processor 301B for establishing dataconnections with a network 307B, such as a local area network coupled toother broadcast system computers and servers or to the Internet.

FIG. 4 illustrates an exemplary wireless communications system 400according to various aspects of the disclosure. In the example of FIG. 4, a UE 404, which may correspond to any of the UEs described above withrespect to FIG. 1 (e.g., UEs 104, UE 182, UE 190, etc.), is attemptingto calculate an estimate of its position, or assist another entity(e.g., a base station or core network component, another UE, a locationserver, a third party application, etc.) to calculate an estimate of itsposition. The UE 404 may communicate wirelessly with a plurality of basestations 402 a-d (collectively, base stations 402), which may correspondto any combination of base stations 102 or 180 and/or WLAN AP 150 inFIG. 1 , using RF signals and standardized protocols for the modulationof the RF signals and the exchange of information packets. By extractingdifferent types of information from the exchanged RF signals, andutilizing the layout of the wireless communications system 400 (i.e.,the base stations locations, geometry, etc.), the UE 404 may determineits position, or assist in the determination of its position, in apredefined reference coordinate system. In an aspect, the UE 404 mayspecify its position using a two-dimensional coordinate system; however,the aspects disclosed herein are not so limited, and may also beapplicable to determining positions using a three-dimensional coordinatesystem, if the extra dimension is desired. Additionally, while FIG. 4illustrates one UE 404 and four base stations 402, as will beappreciated, there may be more UEs 404 and more or fewer base stations402.

Concurrent uplink transmissions by UEs via multiple RATs (e.g., LTE and5G NR via E-UTRAN New Radio—Dual Connectivity or EN-DC mode, or othertypes of dual connectivity modes such as NR-NR NR-LTE, etc.) onparticular band combinations may cause interference (e.g.,intermodulation or IM) on satellite bands, such as Global NavigationSatellite System (GNSS) bands. For example, for any allocated subcarrierfrequencies f1 and f2, uplink transmissions may cause intermodulationinterference if the following conditions are satisfied:(m1×f1+m2×f2>victimFreqStart−freqMargin) AND(m1×f1+f2×g2>victimFreqStop+freqMargin)whereby f1 may represent a first subcarrier frequency of a firstresource block allocated for uplink transmission on a first RAT (e.g.,5G NR, including frequency division duplex (FDD) NR and/or time divisionduplex (TDD) NR), f2 may represent a second subcarrier frequency of asecond resource block allocated for uplink transmission on a second RAT(e.g., LTE), m1 may represent a first intermodulation coefficient, andm2 may represent a second intermodulation coefficient. Further,victimFreqStart may represent a lower frequency boundary of an RFspectrum band that may be subject to intermodulation interference (e.g.,a GNSS spectrum band), victimFreqStop may represent an upper frequencyboundary of the RF spectrum band that may be subject to intermodulationinterference, and freqMargin may represent a configurable frequencymargin value (e.g., 2 MHz, or the like).

In some aspects, an RF spectrum band (e.g., GNSS band) may be associatedwith an interference requirement, such as a requirement that a thresholdnumber of at least 50% “IM free” time across a particular window of time(e.g., 20 ms window). In scenarios where concurrent uplink transmissionson multiple RATs causes IM on such bands, this means that concurrentuplink transmissions on these RATs is limited to no more than 50% of anyparticular window of tie (e.g., no more than 10 ms per 20 ms window).Below, Table 1 indicates particular GNSS bands that may be subjected toIM from particular EN-DC band combinations when used for uplinktransmissions by a particular UE:

TABLE 1 Victim GNSS Bands for 5G NR + LTE Concurrent UplinkTransmissions GPS- GPS- GAL- GLO- BDS- GPS- L5/GAL GLO- BDS- NAV- NameE1 L1 G1 B1 L2 E5a G2 B2 N1 1A- Y(3) Y(3) Y(3) Y(3) n3A 1A- Y(3) Y(3)Y(3) Y(3) n8A 1A- Y(2) Y(2) Y(2) Y(2) Y(2) n28A 2A- Y(3) Y(3) Y(3) Y(3)n5A 2A- Y(3) Y(3) Y(3) Y(3) Y(2) Y(2) Y(2) Y(2) n66A 2A- Y(2) Y(2) Y(2)Y(2) Y(2) n71A 3A- Y(3) Y(3) Y(3) Y(3) n1A 3A- Y(3) Y(3) Y(3) Y(3) Y(3)n8A 7A- Y(2) n8A 12A- Y(2) Y(2) Y(2) n2A 20A- Y(3) Y(3) Y(3) Y(3) Y(3)Y(3) Y(3) n1A 20A- Y(2) Y(2) Y(2) Y(2) n28A 25A- Y(3) Y(3) Y(3) Y(3)Y(3) n41A 30A- Y(3) Y(3) Y(3) Y(3) Y(3) n66A 66A- Y(3) Y(3) Y(3) Y(3)Y(2) Y(2) Y(2) Y(2) n2A 66A- Y(2) n66A 71A- Y(2) Y(2) Y(2) Y(2) Y(2) n2A

In Table 1, Y(2) indicates the presence of 2^(nd) order IM to a victimGNSS band, and Y(3) indicates the presence of 3^(rd) order IM to avictim GNSS band.

FIG. 5 illustrates an exemplary process 500 of managing concurrentmulti-RAT uplink transmissions at a UE. The process 500 of FIG. 5 isperformed by a UE 505, which may correspond to any of the above-notedUEs (e.g., UE 240, 350, etc.).

At 502, the UE 505 (e.g., antenna(s) 352, receiver(s) 354, RX processor356, etc.) receives a first uplink grant for a first RAT (e.g., 5G NR).At 504, the UE 505 (e.g., antenna(s) 352, receiver(s) 354, RX processor356, etc.) receives a second uplink grant for a second RAT (e.g., LTE).

At 506, the UE 505 (e.g., controller/processor 359, etc.) determines anamount of time, over a window of time, that is based on concurrentuplink transmissions on both the first and second RATs. In an example,the amount of time corresponds to a time during which the concurrentuplink transmissions on both the first and second RATs are performed(e.g., during a window of time where GNSS communications are performed).In an alternative example, the amount of time may correspond to a timeduring a victim GNSS is blanked during the window of time (e.g., wherethe victim GNSS band is blanked in slots where the concurrent uplinktransmissions on both the first and second RATs are performed). Ineither case, the amount of time is based on the concurrent uplinktransmissions, irrespective of whether the concurrent uplinktransmissions are factored into the amount of time directly orindirectly via the GNSS blanking. In an example, the determination of506 may be performed by counting the amount of time in particular unitsof time (e.g., slots, half-slots, etc.). In an example, the window oftime may be a moving window of time (e.g., a moving 20 ms window).

At 508, the UE 505 (e.g., controller/processor 359, etc.) determinesthat the amount of time will exceed a time threshold (e.g., 10 ms) if anuplink transmission is performed on the first RAT (e.g., for scenariowhere the amount of time is the GNSS blanking time, the determination of508 assumes that the GNSS will be blanked to account for the first RATtransmission). At 510, the UE 505 (e.g., controller/processor 359, etc.)schedules the uplink transmission on the first RAT based on the amountof time so as to maintain the amount of time where concurrent uplinktransmissions on both the first and second RATs are performed to be lessthan or equal to the time threshold. For example, the scheduling of 510may include dropping at least a portion of the uplink transmission onthe first RAT so as to maintain the amount of time to be less than orequal to the time threshold. In another example, the scheduling of 510may include blanking one or more GNSS communications without droppingany transmission associated with either the first RAT or the second RATin the window of time. In yet another example, the scheduling of 510 mayinclude dropping one or more transmissions over a first set of uplinkchannels on the first RAT while exempting a second set of uplinkchannels on the second RAT from any transmission drops further exemptingany GNSS communications from blanking

Referring to FIG. 5 , in some designs, the UE 505 blanks the GNSS bandduring concurrent multi-RAT transmissions which are not dropped.However, in some designs, the process of FIG. 5 will ensure that thisblanking does not exceed a critical point (e.g., more than 10 ms over a20 ms window) where GNSS will fail due to the dropping that occurs at510.

Referring to FIG. 5 , in some designs, the first RAT is 5GNR and thesecond RAT is LTE. In this case, the scheduled uplink transmissions onthe first RAT (5G NR) or the second RAT (LTE) may occur on the PhysicalUplink Control Channel (PUCCH) or Physical Uplink Shared Channel(PUSCH). In a further example, the scheduled uplink transmissions on thefirst RAT may comprise one or more sounding reference signals (SRSs). Insome designs, a random access channel (RACH) is not factored as part ofthe scheduled uplink transmissions on the first RAT (5GNR) or the secondRAT (LTE) (e.g., because the RACH is limited in terms of resourceblocks, etc.). In other designs, the scheduled uplink transmissions onthe first RAT may include RACH transmissions.

Referring to FIG. 5 , in an example, 5GNR includes the information notedin Table 1 above, with particular EN-DC band combinations and victimsystems (GPS, GLONASS, BDS, Galileo). In some designs, a GNSS indicationof the victim system can be provided to the UE 505 (e.g., in real-time)to indicate when a particular victim system is being utilized. Then, ifthe EN-DC band combination utilized by the first and second RATsinterferes with the indicated victim band, 506-508-510 is triggered.

Referring to FIG. 5 , in some designs, the determination of 506 countsthe amount of time in units of slots, and any concurrent uplinktransmissions in any overlapping slots is counted as a complete overlap.In other designs, the determination of 506 counts the amount of time inunits shorter than a length of a slot (e.g., a half-slot, etc.) tofactor whether any overlapping slots overlap completely or partially.

Referring to FIG. 5 , in some designs, a first timing of time slotscarrying respective resource blocks on the first RAT being offset from asecond timing of time slots carrying respective resource blocks on thesecond RAT. For example, a scenario may occur where there is 100%scheduling on 5G NR and 50% scheduling on LTE with 0.5 ms offset (e.g.,half of a 1 ms slot) between the two. In this case, a count unit ofgranularity for 506 of FIG. 5 may be a half-slot.

FIGS. 6A-6B illustrate scenarios where timings for RATs 1 and 2 areoffset from each other by a half-slot. In FIG. 6A, each partial overlapis counted as a complete overlap (e.g., if only half of a RAT 1 slotoverlaps with a RAT 2 transmission, then RAT 1 slot is deemed tocompletely overlap with RAT 2). This causes the overlap count toincrease more quickly, resulting in a dropped RAT 1 transmission at slot600A. In FIG. 6B, partial overlaps are considered (e.g., if only half ofa RAT 1 slot overlaps with a RAT 2 transmission, only half of that RAT 1slot is deemed to overlap with RAT 2). This causes the overlap count toincrease less quickly, such that a RAT 1 transmission at slot 600B(which corresponds to slot 600A of FIG. 6A) is not dropped.

FIGS. 7A-7B illustrate scenarios where timings for RATs 1 and 2 areoffset from each other by a half-slot. In FIGS. 7A-7B, it is assumedthat RAT 1 is scheduled without knowledge of RAT 2's transmissionschedule. As shown in FIG. 7A, RAT 1 begins a transmission at slot 700A,which then overlaps with a RAT 2 transmission starting a half-slotlater, at which point the amount of time where concurrent uplinktransmissions on both the first and second RATs are scheduled over thewindow of time is exceeded (e.g., causing IM to impact the GNSS band).In FIG. 7B, an intra-slot transmission drop is implemented. In thiscase, by counting at partial slot increments (e.g., half-slot), a latterpart of a scheduled RAT 1 transmission can be dropped (or cutoff) suchthat the time threshold for concurrent multi-RAT transmissions is notexceeded, as shown with respect to RAT 1 slot 700B of FIG. 7B (e.g.,first half of RAT 1 slot 700B includes the scheduled RAT 1 transmissionfor that slot, while second half of RAT 1 slot is dropped 700B). In FIG.7B, the drop decision of 510 of FIG. 5 is made at the symbol level(e.g., at each half-slot) instead of the slot level as in FIGS. 6A-6B.

In some designs, the determination of 506 of FIG. 5 may use a cyclicbitmap of 40 bits (e.g., 2 bits per slot in 20 ms for 15 kHz SCS). Inthis example, each bit indicates whether there was IM in a half-slotcaused by RATs 1 and 2 transmitting concurrently in that half-slot. In aspecific example, if RAT 1 corresponding to 5G NR and RAT 2 correspondsto LTE, then an exemplary algorithm for updating the 40-bit cyclicbitmap at each half-slot is as follows:

-   -   When 5G NR attempts to schedule a new transmission in a        half-slot:        -   If the bitmap has 20 is or more (without counting a present            bit position) and LTE has a concurrent transmission on any            symbol of this half-slot:            -   drop the new 5G NR transmission, set the present bit                position to 0, remove oldest bit position, and do not                blank GNSS,        -   Else if LTE has a concurrent transmission on any symbol of            this half-slot:            -   Do not drop the new 5G NR transmission, set the present                bit position to 1, remove oldest bit position, and blank                GNSS,        -   Else:            -   Do not drop the new 5G NR transmission, set present bit                position to 0, and do not blank GNSS,    -   When 5G NR does not attempt to schedule anew transmission in a        half-slot:        -   Set present bit position to 0, and do not blank GNSS,

In another specific example, if RAT 1 corresponding to 5G NR and RAT 2corresponds to LTE, GNSS may be blanked in up to 50% of slots where 5GNR transmits. In the remaining slots, 5G NR tries best effort totransmit, and if LTE overlaps, then 5G NR stops transmitting. In thisexample, assume that a cyclic bitmap of 20 bits is used (e.g., 1 bit perslot in 20 ms for 15 kHz SCS). Each bit of the 20-bit cycling bitmapindicates whether GNSS was blanked in a respective slot. A 5G NRtransmission is blanked if a concurrent LTE transmission is scheduled,and if GNSS blanking exceeds 10 ms in a moving 20 ms window of time. 5GNR transmission dropping is performed intra-slot, whereas GNSS blanking(if used) is performed only once per slot. Under these assumptions, anexemplary algorithm for updating the 20-bit cyclic bitmap at each slotis as follows:

-   -   Bitmap bit set to 1 if        -   GNSS blanked    -   GNSS blanked if        -   Bitmap does not have 10 is in previous 20 positions,    -   5G NR transmission scheduled (on a respective half-slot) if        -   Bitmap does not have 10 is in previous 20 positions, or        -   Bitmap has 10 is in previous 20 positions and no LTE            transmission in this half-slot

A more detailed version of the above-noted exemplary algorithm forupdating the 20-bit cycling bitmap at each slot is as follows:

-   -   First half-slot of slot, when 5G NR schedules a transmission:        -   If the bitmap has 10 is (without counting the present bit            position),            -   If there is a concurrent LTE transmission (any symbol of                this half-slot)                -   Drop 5G NR transmission,            -   Else                -   Continue with 5G NR transmission scheduling    -   Mid-Slot, when 5G NR schedules a transmission:        -   If there is a concurrent LTE transmission (any symbol of            this half-slot)            -   Drop 5G NR transmission        -   Else (5G NR has no transmission)            -   Set bit to 0

FIGS. 7C-7D illustrate scenarios where timings for RATs 1 and 2 areoffset from each other by a half-slot whereby RAT 1 corresponds to 5G NR(or simply NR) and RAT 2 corresponds to LTE. In FIGS. 7C-7D, GNSS isblanked in up to 50% of slots where NR transmits, and NR uses besteffort to transmit in any remaining slots (if there is an overlappingLTE transmission that would cause GNSS blanking to exceed 50%, then NRtransmission is dropped).

Referring to FIG. 5 , in some designs, concurrent multi-RATtransmissions are permitted without the restriction of the timethreshold in some scenarios, such as when no victim GNSS band is beingutilized. In a further example, even when a victim GNSS band is beingutilized, a separate power analysis may be performed before triggeringthe process of FIG. 5 .

In an example, a power threshold beyond which concurrent multi-RATtransmissions cause IM-related problems to particular victim GNSS bandsis determined. In some designs, if a total power (e.g., in dBm) for RATs1 and 2 (e.g., LTE+5G NR) exceeds this power threshold, then the processof FIG. 5 may be executed. In other designs, the total power for RATs 1and 2 may be regulated in accordance with a power backoff protocol toensure that the total power is not exceeded. However, if the total power(e.g., in dBm) for RATs 1 and 2 (e.g., LTE+5G NR) does not exceed thispower threshold (e.g., in accordance with ‘normal’ power controlprotocols or in accordance with a power backoff protocol which lowersthe total power below the power threshold), then the process of FIG. 5is not executed and RATs 1 and 2 are permitted to schedule transmissionwithout regard to their impact to a victim GNSS band. In some designs,if the total power (e.g., in dBm) for RATs 1 and 2 (e.g., LTE+5G NR)exceeds the power threshold, the UE may also fill in the UL grant forRAT 1 with MAC ‘padding’ so as to avoid loss of data resulting from thepower backoff.

In a further example, 506-508-510 of FIG. 5 may be triggered based onone or more conditions. In one specific example, the one or moreconditions may include an uplink duty cycle in TDD. For instance, if theuplink duty cycle is greater than a threshold (e.g., 50%, etc.), thenthe 506-508-510 of FIG. 5 are performed; if not, transmissions may bepermitted on the first RAT without dropping any associated packets.

While FIGS. 5-7B are generally directed to selective dropping ofscheduled uplink transmission on a particular RAT (e.g., 5G NR), furtherembodiments are directed to reducing a number of drops via buffer statusreport (BSR) management. For example, reducing the number of drops toscheduled transmissions will result in less HARQ loss and RLC levelrecovery. Also, for split bearers, data can be sent on RAT 2 (e.g., LTE)instead of being stuck in a 5G NR HARQ that experiences a high number ofdrops.

In some designs, a BSR is used to indicate an amount of UL data fortransmission over 5G NR. The BSR reports only enough data so as toachieve a target data rate, R, in a time period defined as a transmitperiod (e.g., an amount of time at which the traffic volume specified bythe BSR would be drained at target data rate R). In some designscooldown period T_c in which no BSR is reported, and padding is sent.For an initial BSR, IR=T_c*R (e.g., so as to drain the original amountof data during T_c). After this initial period, the BSR is updated byBSR(t)=BSR(t−1)−Grant(t−1)+R*TTI (e.g., so as to drain the originalamount of data minus previous grant plus data accumulated during 1 TTI).

FIG. 8 illustrates an exemplary process 800 of managing concurrentmulti-RAT uplink transmissions at a UE. The process 800 of FIG. 8 isperformed by a UE 805, which may correspond to any of the above-notedUEs (e.g., UE 240, 350, etc.).

At 802, the UE 805 (e.g., antenna(s) 352, receiver(s) 354, RX processor356, etc.) receives a first uplink grant for a first RAT (e.g., 5G NR).At 804, the UE 805 (e.g., antenna(s) 352, receiver(s) 354, RX processor356, etc.) receives a second uplink grant for a second RAT (e.g., LTE).At 806, the UE 805 (e.g., controller/processor 359, etc.) establishes afirst period of time where a buffer status report (BSR) transmitted bythe UE on the first RAT is adjusted to reflect an amount of data thatcan be drained in an amount of time (e.g., no more than 10 ms over a 20ms window) where concurrent uplink transmissions on both the first andsecond RATs are permitted to be scheduled. At 808, the UE 805 (e.g.,controller/processor 359, etc.) establishes a second period of timewhere no BSR is transmitted by the UE on the first RAT based on a timethreshold (e.g., 10 ms) associated with an amount of time (e.g., no morethan 10 ms over a 20 ms window) where concurrent uplink transmissions onboth the first and second RATs are not permitted to be scheduled. Asused herein, no BSR being reported or transmitted refers to a scenariowhere the BSR is not transmitted at all, or alternatively to a scenariowhere the BSR indicating a traffic volume of zero is transmitted.

An example implementation of the process of FIG. 8 will now be describedspecific to a 15 kHz numerology whereby the first RAT is 5G NR and thesecond RAT is LTE. In this example, T_c=10 ms, and IR=10 ms*R. At everyslot, BSR(t)=BSR(t−1)−Grant(t−1)+R*1 ms. For all logical channel groups(LCGs) reported on 5G NR:

-   -   Split bearer (e.g., a bearer which is transmitted and received        via both the master and secondary base stations): scale (or        adjust) 5G NR BSR,    -   Secondary cell group (SCG) bearer (or split bearer) configured        to send only on NR: scale (or adjust) 5G NR BSR only if LTE BSR        is non-zero or never scale for simplicity.

For example, the adjustment of 806 may be done only for BSR associatedwith a split bearer. In another example, the adjustment of 806 may bedone for SCG bearer or split bearer configured to send only on NR if theBSR reported on the second RAT is non-zero. In some designs, for 5G NRstandalone (SA) mode, if the component carriers utilized by PCell andSCell(s) cause IM to a victim GNSS band, then the UE can implement aprocess similar to the process of FIG. 5 . So, the UE can count theconcurrent NR PCell and SCell transmissions in a window of time (e.g.,20 ms), and then drop SCell transmissions so as to permit a definedamount of IM-free time (e.g., 10 ms or more, or at least 50% of IM-freetime) for the victim GNSS band. In a further example, emergency callpositioning in 5G NR SA mode may be similar to LTE (e.g., SCell ULtransmissions dropped if concurrent with PCell UL transmissions).

In further designs, additional optimizations can be implemented beyondselective dropping of scheduled 5G NR uplink transmissions. In oneexample, scheduled LTE uplink transmissions can be blanked preemptivelyin order to grant a higher priority to scheduled 5G NR uplinktransmissions (e.g., to reduce drops to 5G NR). In another example,certain higher priority 5G NR traffic can be exempted from drops. Forexample, PUCCH carrying HARQ feedback on 5G NR can be exempted, with LTEtraffic being dropped instead if necessary to protect the victim GNSSband pursuant to the process of FIG. 5 . In a more specific example,only a PUCCH allocated a number of resource blocks falling below athreshold number of resource blocks is exempted, while a PUCCH includingat least the threshold number of resources blocks and/or one or moreother non-PUCCH uplink channels are not exempted. In a further example,the UE can check for exact resource blocks in the UL grant if it causesIM (e.g., define overlap more precisely in terms of both frequency andtime instead of time only). In a further example, for an emergency callwhere GNSS is needed, a rule can be implemented whereby only concurrent5G NR uplink transmissions are dropped. In a further example, amini-slot could be implemented whereby scheduling is possible in fewerthan 14 symbols. In such an implementation, partial slot counting at afiner granularity (e.g., fewer than 7 symbols, or a normal ‘half-slot’)can be implemented.

In further designs, a GNSS requirement may be defined for particularhigher-priority calls, such as emergency calls which may be conductedover LTE. In this case, if a UE is using EN-DC on IM band combinations,an emergency call handling protocol may be implemented. For example, anyscheduled uplink transmissions on 5G NR that are concurrent withtransmissions on LTE while the emergency call is active are dropped.Alternatively, the 5G NR may be released (e.g., SCG failure) to preventany IM interference to GNSS. Alternatively, a lower time threshold canbe used during the emergency call (e.g., 5 ms instead of 10 ms, etc.) sothat more 5G NR SCell transmissions are dropped without requiring all 5GNR uplink transmissions to be dropped. Similarly, in 5G NR SA mode andan emergency call is being conducted, any SCell UL transmissions thatare concurrent transmissions with PCell UL transmissions may be dropped.Alternatively, a lower time threshold can be used during the emergencycall (e.g., 5 ms instead of 10 ms, etc.) so that more SCell ULtransmissions are dropped without requiring all SCell UL transmissionsto be dropped.

In further designs, the various operations described above with respectto FIGS. 5 and 8 may be implemented via various “means”, such asparticular hardware components of the associated UEs 505 and 805. Forexample, means for performing the receiving aspects of 502, 504, 802 and804 may correspond to any combination of receiver-related circuitry onthe respective UEs, such as antenna(s) 352, receiver(s) 354, RXprocessor 356, etc. of UE 350 of FIG. 3A. In a further example, meansfor performing the determining, scheduling and establishing aspects of506, 508, 806 and 808 may corresponding to any combination ofprocessor-related circuitry on the respective UEs, such ascontroller/processor 359 of UE 350 of FIG. 3A.

While some of the embodiments are described above with respect to EN-DCmode, the various embodiments of the disclosure are also applicable withrespect to other types of dual connectivity modes, such as such as NR-NRNR-LTE, etc. Moreover, while some of the embodiments are described withrespect to specific numerologies (e.g., 15 kHz SCS), other embodimentsmay be directed to implementations whereby different numerologies areused (e.g., 30 kHz SCS, 60 kHz SCS, 120 kHz SCS, 240 kHz SCS, 480 kHzSCS, etc.).

Those skilled in the art will appreciate that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Further, those skilled in the art will appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the aspects disclosed herein may beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such implementation decisions should not be interpreted to departfrom the scope of the various aspects described herein.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or other suchconfigurations).

The methods, sequences, and/or algorithms described in connection withthe aspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in RAM, flash memory, ROM, EPROM, EEPROM,registers, hard disk, a removable disk, a CD-ROM, or any other form ofnon-transitory computer-readable medium known in the art. An exemplarynon-transitory computer-readable medium may be coupled to the processorsuch that the processor can read information from, and write informationto, the non-transitory computer-readable medium. In the alternative, thenon-transitory computer-readable medium may be integral to theprocessor. The processor and the non-transitory computer-readable mediummay reside in an ASIC. The ASIC may reside in a user device (e.g., a UE)or a base station. In the alternative, the processor and thenon-transitory computer-readable medium may be discrete components in auser device or base station.

In one or more exemplary aspects, the functions described herein may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on a non-transitorycomputer-readable medium. Computer-readable media may include storagemedia and/or communication media including any non-transitory mediumthat may facilitate transferring a computer program from one place toanother. A storage media may be any available media that can be accessedby a computer. By way of example, and not limitation, suchcomputer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code in the form of instructions or data structures and that canbe accessed by a computer. Also, any connection is properly termed acomputer-readable medium. For example, if the software is transmittedfrom a website, server, or other remote source using a coaxial cable,fiber optic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave, then the coaxial cable, fiber opticcable, twisted pair, DSL, or wireless technologies such as infrared,radio, and microwave are included in the definition of a medium. Theterm disk and disc, which may be used interchangeably herein, includesCD, laser disc, optical disc, DVD, floppy disk, and Blu-ray discs, whichusually reproduce data magnetically and/or optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

While the foregoing disclosure shows illustrative aspects, those skilledin the art will appreciate that various changes and modifications couldbe made herein without departing from the scope of the disclosure asdefined by the appended claims. Furthermore, in accordance with thevarious illustrative aspects described herein, those skilled in the artwill appreciate that the functions, steps, and/or actions in any methodsdescribed above and/or recited in any method claims appended hereto neednot be performed in any particular order. Further still, to the extentthat any elements are described above or recited in the appended claimsin a singular form, those skilled in the art will appreciate thatsingular form(s) contemplate the plural as well unless limitation to thesingular form(s) is explicitly stated.

What is claimed is:
 1. A user equipment (UE), comprising: a memory; atleast one transceiver; and at least one processor coupled to the memoryand the at least one transceiver and configured to: receive, via the atleast one transceiver, an uplink grant for a first radio accesstechnology (RAT); schedule an uplink transmission on the first RAT basedon an amount of time so as to maintain an amount of time whereconcurrent uplink transmissions on both the first RAT and a second RATare performed to be less than or equal to a time threshold; and schedulethe uplink transmission on the first RAT in response to the first RAToperating in accordance with time division duplex (TDD) with an uplinkduty cycle that is greater than a threshold.
 2. The UE of claim 1,wherein the amount of time corresponds to a time during whichcommunications on a victim frequency band are blanked during the windowof time, or wherein the amount of time corresponds to a time duringwhich the concurrent uplink transmissions on both the first and secondRATs are performed.
 3. The UE of claim 2, wherein the at least oneprocessor blanks the victim frequency band is blanked in slots where theconcurrent uplink transmissions on both the first and second RATs areperformed.
 4. The UE of claim 1, wherein the amount of time is based ona time overlap of resource blocks allocated to the concurrent uplinktransmissions on the first and second RATs, or wherein the amount oftime is based on a time and frequency overlap of resource blocksallocated to the concurrent uplink transmissions on the first and secondRATs.
 5. The UE of claim 1, wherein the at least one processor maintainsthe amount of time where concurrent uplink transmissions on both thefirst and second RATs are performed to be less than or equal to the timethreshold by dropping one or more transmissions over a first set ofuplink channels on the first RAT while exempting a second set of uplinkchannels from any transmission drops.
 6. The UE of claim 5, wherein thesecond set of uplink channels includes a physical uplink control channel(PUCCH), or wherein the second set of uplink channels includes a PUCCHallocated a number of resource blocks that is less than a threshold. 7.The UE of claim 1, wherein the at least one processor is furtherconfigured to (i) drop uplink transmissions on the first RAT so long asa higher-priority communication session is supported over the secondRAT, or (ii) drop the first RAT so long as the higher-prioritycommunication session is supported over the second RAT.
 8. The UE ofclaim 1, wherein the amount of time is defined in units of slots, andany concurrent uplink transmissions in any overlapping slots is acomplete overlap, or wherein the amount of time is defined in unitsshorter than a length of a slot to factor whether any overlapping slotsoverlap completely or partially.
 9. The UE of claim 1, wherein a firsttiming of time slots carrying respective resource blocks on the firstRAT being offset from a second timing of time slots carrying respectiveresource blocks on the second RAT, wherein the amount of time is definedin units shorter than a length of a slot, and wherein the at least oneprocessor is further configured to drop some or all of a remainder ofthe uplink transmission on the given slot of the first RAT so as tomaintain the amount of time to be less than or equal to a timethreshold.
 10. The UE of claim 1, wherein the at least one processor isfurther configured to implement a power backoff to one or moreconcurrent uplink transmissions on both the first and second RATs suchthat a total power is maintained at less than or equal to a powerthreshold.
 11. The UE of claim 1, wherein the first RAT is 5G New Radio(NR), and wherein the second RAT is Long Term Evolution (LTE).
 12. Amethod of operating a user equipment (UE), comprising: receiving, via atleast one transceiver, an uplink grant for a first radio accesstechnology (RAT); scheduling an uplink transmission on the first RATbased on an amount of time so as to maintain an amount of time whereconcurrent uplink transmissions on both the first RAT and a second RATare performed to be less than or equal to a time threshold; andscheduling the uplink transmission on the first RAT in response to thefirst RAT operating in accordance with time division duplex (TDD) withan uplink duty cycle that is greater than a threshold.
 13. The method ofclaim 12, wherein the amount of time corresponds to a time during whichcommunications on a victim band are blanked during the window of time,or wherein the amount of time corresponds to a time during which theconcurrent uplink transmissions on both the first and second RATs areperformed.
 14. The method of claim 13, wherein the victim frequency bandis blanked in slots where the concurrent uplink transmissions on boththe first and second RATs are performed.
 15. The method of claim 12,wherein the amount of time is based on a time overlap of resource blocksallocated to the concurrent uplink transmissions on the first and secondRATs, or wherein the amount of time is based on a time and frequencyoverlap of resource blocks allocated to the concurrent uplinktransmissions on the first and second RATs.
 16. The method of claim 12,wherein the scheduling drops one or more transmissions over a first setof uplink channels on the first RAT while exempting a second set ofuplink channels on the second RAT from any transmission drops.
 17. Themethod of claim 16, wherein the second set of uplink channels includes aphysical uplink control channel (PUCCH), or wherein the second set ofuplink channels includes a PUCCH allocated a number of resource blocksthat is less than a threshold.
 18. The method of claim 12, wherein thescheduling drops one or more uplink transmissions on the first RAT solong as a higher-priority communication session is supported over thesecond RAT, or wherein the scheduling drops the first RAT so long as thehigher-priority communication session is supported over the second RAT.19. The method of claim 12, wherein the amount of time is defined inunits of slots, and any concurrent uplink transmissions in anyoverlapping slots is a complete overlap, or wherein the amount of timeis defined in units shorter than a length of a slot to factor whetherany overlapping slots overlap completely or partially.
 20. The method ofclaim 12, wherein a first timing of time slots carrying respectiveresource blocks on the first RAT being offset from a second timing oftime slots carrying respective resource blocks on the second RAT,wherein the amount of time is defined in units shorter than a length ofa slot, and wherein the scheduling drops some or all of a remainder ofthe uplink transmission on the given slot of the first RAT so as tomaintain the amount of time to be less than or equal to a timethreshold.